Química


Aspirin


Analysis of ASA

Aspirin or acetylsalicylic acid is a derivative of salicylic acid that is a mild, no narcotic analgesic useful in the relief of headache and muscle and joint aches. The drug works by inhibiting the production of prostaglandins, body chemicals that are necessary for blood clotting and which also sensitize nerve endings to pain.

History/ Discovery of ASA

The father of modern medicine was Hippocrates, who lived sometime between 460 B.C and 377 B.C. Hippocrates has left historical records of pain relief treatments, including the use of powder made from the bark and leaves of the willow tree to help heal headaches, pains and fevers. By 1829, scientists discovered that it was the compound called salicin in willow plants which gave pain relief.

According to “From A Miracle Drug” written by Sophie Jourdier for the Royal Society of Chemistry: “It was not long before the active ingredient in willow bark was isolated; in 1828, Johann Buchner, professor of pharmacy at the University of Munich, isolated a tiny amount of bitter tasting yellow, needle-like crystals, which he called salicin. Two Italians, Brugnatelli and Fontana, had in fact already obtained salicin in 1826, but in a highly impure form. By 1829, [French chemist] Henri Leroux had improved the extraction procedure to obtain about 30g from 1.5kg of bark. In 1838, Raffaele Piria [an Italian chemist] then working at the Sorbonne in Paris, split salicin into a sugar and an aromatic component (salicylaldehyde) and converted the latter, by hydrolysis and oxidation, to an acid of crystallised colourless needles, which he named salicylic acid.”

Henri Leroux had extracted salicin, in crystalline form for the first time, and Raffaele Piria succeeded in obtaining the salicylic acid in its pure state.

In 1899, a German chemist named Felix Hoffmann, who worked for a German company called Bayer, rediscovered Gerhardt's formula, the first person to neutralize salicylic acid by buffering it with sodium(sodium salicylate) and acetyl chloride), creating acetylsalicylic acid. Felix Hoffmann made some of the formula and gave it to his father who was suffering from the pain of arthritis. With good results, Felix Hoffmann then convinced Bayer to market the new wonder drug. Aspirin was patented on March 6, 1889.

Aspirin was first sold as a powder. In 1915, the first Aspirin tablets were made. Interestingly, Aspirin ® and Heroin ® were once trademarks belonging to Bayer. After Germany lost World War I, Bayer was forced to give up both trademarks as part of the Treaty of Versailles in 1919.

Uses / problems

Aspirin is used to relieve mild to moderate pain; reduce fever, redness, and swelling; and to help prevent blood from clotting. It is used to relieve discomfort caused by numerous medical problems, including headache, infections, and arthritis. It also is used to reduce the risk of a second heart attack or stroke. Larger doses of aspirin are used to treat gout.
Based on clinical research, only a small number of individuals (5%) who use ASPIRIN have experienced stomach upset. People who experience stomach irritation should ask their doctor whether an enteric coated product or buffered product might help reduce stomach-related side effects

ASA toxicity: (dose-dependent) (more common & serious in children than in adults.)

  • Low-doses (2-4g/day). GI intolerance, bleeding, Hypersensitivity reactions (rash), asthma, hemostases impairment.

  • Moderate doses (salicylism): Central hyperventilation, Tinnitus, vertigo, vomiting

  • Very high doses: Metabolic acidosis, Fever, dehydratation, Vasomotor collapses, coma, Renal and respiratory failure

.

Mechanism of action

Nobel Prize winner Sir John Vane discovered in 1971 that acetylsalicylic acid (ASA) inhibits the biosynthesis of certain messenger molecules known as prostaglandins. These prostaglandins perform a number of different functions in the body. They play a particularly important role in the processes of pain and inflammation, in which they act as mediators. They are formed whenever a cell is damaged or even destroyed by factors such as mechanical effects, heat or aggressive chemicals. When damage such as this occurs, the fatty acid arachidonic acid is released from the cell membrane. Prostaglandins are immediately synthesized from this substance with the aid of two enzymes. ASA inhibits the activity of both of these enzymes, thus preventing the biosynthesis of pain-exacerbating and pro-inflammatory prostaglandins.

Manufacturing

Making the reactants of the aspirin synthesis the products of other reactions

'Aspirin'
Social/ Economic impact

Aspirin has been shown to be a highly cost-effective therapy for primary prevention patients, aged 30-80 with a 10-year risk of coronary heart disease ranging from 5-20%

Analysis of an ASA tablet

References

Books

Feinman, S. E. (Ed.). Beneficial and toxic effects of aspirin. CRC Press, Boca Raton,FL; 1993.

Mann CC, Plummer ML. The Aspirin Wars: Money, Medicine, and 100 Years of Rampant Competition. Boston: Harvard Business School Press; 1991.

Vane JR, Botting RM. Aspirin and other Salicylates. London: Chapman and Hall Medical Publishers; 1992.

Verg E, Plumpe G, Schultheis H. Meilensteine: The official Bayer publication in commemoration of the centenary of aspirin's release; 1989.

Web sites

Alka-Zseltzer ,(n.d) Aspirin .Retriever December 26,2003 from http://www.medicine.mcgill.ca/mjm/issues/v02n02/aspirin.htm

Mary Bellis (2003) History of Aspirin , Retrieved December 26, 2003 from http://inventors.about.com/library/inventors/blaspirin.htm

Aspirin in prevention in blood clot formation. Retrieved January 3 , 2004 from

http://www.mbb.ki.se/research/kemi_2/proteomics_ppt/Aspirin.pd

Treatment on-line. Retrieved January 3,2004 from http://3.buy-cheap-adipex.com/asa_aspirin.html

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Enviado por:Tu Salvacion
Idioma: inglés
País: Estados Unidos

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